Pile protector



NOV. 24, 1970 w, W K ETAL 3,541,800

I PILE PROTECTOR Filed Sept; 17, 1968 I mam/4, ceomsu a WEAVER N VENTORE.

United States Patent Ofice Patented Nov. 24, 1970 3,541,800 PILE PROTECTOR Grant W. Walker, 4339 Lantzy Court, Sacramento, Calif.

95825, and Duane B. Ford, 2811 Hocking St., Placerville, Calif. 95667 Filed Sept. 17, 1968, Ser. No. 760,142 Int. Cl. E02b 3/22 US. Cl. 6148 7 Claims ABSTRACT OF THE DISCLOSURE A pile protector comprising a rigid housing surrounding the pile to be protected in spaced relation therefrom and upper and lower non-energy storing collapsible assemblies filling the space between the pile and the rigid housing for being collapsed without significant storage of energy upon impact of a vessel with the rigid housing, the collapsible assemblies normally containing water which is expelled at a rate commensurate with the severity of impact is disclosed.

BACKGROUND OF THE INVENTION Field of the invention Thi invention relates to static structures, such as bridge pilings, dock pilings, and other constructions which are supported over bodies of water by piling or the equivalent. More particularly, this invention relates to devices for preventing damage to piles and structures including piling from collision by vessels in the body of water.

Description of the prior art It is fairly conventional to provide protective devices around vertical members. Sometimes such constructions are provided to prevent injury to persons who might collide therewith, such as goal post padding of the type described by Doyle in US. Pat. No. 3,104,875. It is also fairly common to provide protective devices for piers, pilings, and the like. Such devices are often energy storing and rely on springs or pneumatic devices to prevent direct transmission of impact energy from a colliding vessel to the pile to be protected. Such devices are often adapted to ride up and down the pile as the tide or waves rise and fall. One device of this type is described by Slemmons in US Pat. No. 3,055,182. It is to 'be noted that energy storing rubber sandwiches are used in the Slemrnons system for protecting wharves, piers, etc.

While resilient or otherwise energy storing devices are effective to prevent sharp transmission of impact energy from a colliding vessel to the pier or pile, to be protected, such devices are often ineffective or incompletely effective because the energy is simply stored up and is transmitted directly or indirectly to the structure to be supported. Similarly, the stored energy may cause injury to persons on the colliding vessel or damage thereto. It is, therefore, a principal object of this invention to provide an improved protective construction for piles and the like.

SUMMARY OF THE INVENTION The present invention comprises a construction for dissipating impact energy resulting from collision or potential collision to vessels with bridge supporting piles, dock supporting piles, and the like. The pile protective construction of this invention generally comprises rigid means for substantially surrounding the pile to be profected in spaced relation therefrom for free limited angular motion relative to the pile and two or more vertically spaced non-energy storing collapsible means for substantially surrounding the pile to be protected in the space between the pile and the rigid means. The collapsible means are so constructed and disposed in the space as to contact the pile and the rigid means at upper and lower points for being collapsed without significant energy storage and at a rate commensurate with the severity of impact energy transmitted to the rigid means by collision with a vessel. It is a principal object of this invention to provide an energy dissipating pile protective construction,

A more specific object of the invention is the provision of a buoyant energy dissipating pile protective construction.

A further object of the invention is to provide a construction in which liquid is expelled from cylindrical members only at a rate commensurate with impact energy. Other objects of the invention will be apparent from the specification which follows and from the drawings to which reference is now made.

FIG. 1 is a top plan view of the construction of this invention shown in position around a bridge pile.

FIG. 2 is a side elevational view, partially cut away, showing the interior configalratiou of the pier protective construction of this invention.

FIG. 3 illustrates the operation of the present invention.

The pile 10 Which is to be protected is surrounded or substantially surrounded by the pile protective construction shown generally at 12 which preferably floats upon or is supported adjacent the water level 14.

The pile protective construction comprises the combination of a generally rigid means 16 for substantially surrounding the pile to be protected in spaced relation therefrom to permit free limited angular motion relative to the pile in response to a collision force indicated at F above the water line 14. At least two relatively vertically spaced non-energy storing collapsible means 18 and 20 for substantially surrounding the pile to be protected in the space between the pile and the rigid means are provided. These collapsible means are secured to the rigid means in the respective relative positions indicated. Three, or more, such collapsible means may be used but two are generally sufficient. The collapsible means is so constructed and disposed in the space as to contact the pile and the rigid means at upper and lower points for being collapsed, as indicated at 18A and 20A without significant storage of energy and for being collapsed at a rate commensurate with the severity of impact energy, F, transmitted to the rigid means upon collision therewith by a vessel.

As best shown in FIGS. 1 and 2, the rigid means comprises a plurality of vertical shafts, such as treated poles or small piles, 22, 22A, etc. These vertical shafts 22 are secured together to substantially surround the pile 10 by securing means 24, .26, and 28 which may be in the form of wood or steel ring members. Generally, the securing :means are adapted to permit partial construction of the rigid means prior to transportation to the site of use and completed construction on site.

Inside the rigid means 16 there are disposed a large multiplicity of cylinders 30, 30A, etc., and, there below, cylinders 32, 32A, etc. forming, respectively, the collapsible means 18 and 20. These cylinders are secured together by cables 34 in the upper collapsible means and 36 in the lower collapsible means. Other securing means to permit collapse are equally satisfactory and regarded as equivalent.

The cylinders 30 and 3-2 are of the type described by John W. Rich in co-pending applications Ser. No. 664,333, filed Aug. 30, 1967, and may, more particularly, be of the type illustrated in FIGS. 6-10 of said application, the entire disclosure and drawings of which are incorporated herein by reference for complete description.

For present clarity, however, these cylindrical members are easily described and can be envisioned as vertical cylinders having closed top members and bottom members which define one or more apertures. The cylinders are formed of essentially non-energy storing resilient material so that they can be collapsed easily upon the exertion of impact force. These cylinders normally contain an incompressible liquid; in the present application this would normally be water. The water may completely or only partially fill the cylinders. Upon impact of a vessel with the rigid means, the impact energy is transmitted to the collapsible means, i.e. the multiplicity of cylinders. The cylinders, of the type described in the aforementioned application of John W. Rich, collapse under the exertion of the impact force, thereby forcing the water to flow outwardly through the orifice in the bottom of the cylinder. The orifice, as more completely described in the aforementioned application, is so disposed and constructed as to permit outflow of the water at a rate only commensurate with the severity of impact energy applied thereto. By this means, the energy of impact is not stored up, as is the case in the prior art devices, but is rather dissipated. Thus, the energy is not transmitted to the pile nor is it retransmitted to the vessel after the initial impact, as is the case with energy storing resilient devices.

It will be understood that these cylinders are made of mildly resilient material and will very slowly return to their original configuration; that is, they are normally shape-retaining but return to the normal configuration only very slowly. For example, it may take several minutes for the cylinders to return to their original configuration following impact with a vessel.

As a result of this unique non-energy storing construction, damage results neither to the pile, the construction supported by the pile, nor to the vessel. Thus, a new and vastly improved result is obtained as compared with the devices of the prior art.

As previously indicated, it is desired that the protective construction be so constructed as to be buoyantly supported by the water. This is simply a matter of recognizing engineering to provide a construction having, overall, less density than that of water. For example, the shafts are conventionally made of poles or logs which have been treated for water and insect resistance and are, therefore, buoyant. These poles, by proper treatment and selection, may be sufiiciently buoyant to support the collapsible means.

Similarly, using the principles set forth in the aforementioned application of John W. Rich, the collapsible cylinders may contain sufficient air to provide buoyancy sufiicient to support both the collapsible means and the rigid means, i.e. the pier protective construction. Obviously, both the rigid means and the collapsible means may be buoyant if desired.

From the foregoing, it will be apparent that an improved pile protective construction has been provided which may be applied to pilings associated with piers, etc., and marine structures in general; however, one of the most important applications of this pile protective construction is in association with bridge supporting piles and the like. It is, for example, fairly common to build bridges spanning navigable lakes, bays, rivers, and other bodies of water. It is essential that means be provided to prevent severe damage to these structures since loss of life, along with extreme damage to property, may result from a bridge collapse following collision by a vessel.

In a particular embodiment, the shafts may be from ten to thirty feet in length, but generally would not exceed about fifteen to twenty feet and may be spaced from five to fifteen feet away from the pile, preferably around five to ten feet therefrom to permit limited angular movement with respect to the pile. The cylinders are of the construction described in the aforementioned John W. Rich application and may, generally, be approximately six inches in diameter and from three to six feet in length. Obviously, the exact dimensions are not critical to the invention and such dimensions will be adapted to the size of the pile to be protected, the size of the body of water, and size of vessels therein, etc.

From the foregoing, design and use of the invention will be apparent to those skilled in the art and it is intended that the illustrations given herein form the basis for the exercise of conventional engineering skills in adapting the constructions of this invention to the su gested and analogous uses. It is not intended, however, that the examples or embodiments given herein be considered limiting since many variations, modifications, and changes may be made based upon the principles set forth herein before without departing from the spirit and scope of the invention as defined in the following claims.

We claim:

1. A pile protective construction comprising, in combination:

generally rigid means for substantially surrounding the pile to be protected in spaced relation for free limited angular motion relative to the pile; and

at least two relatively vertically spaced non-energy storing collapsible means for substantially surrounding the pile to be protected in the space between said pile and said rigid means, said collapsible means being so constructed and disposed in said space as to contact the pile and the rigid means at upper and lower points for being collapsed without significant storage of energy at a rate commensurate with the severity of an impact energy transmitted to the rigid means upon collision therewith by a vessel.

2. The pile protective construction of claim 1 wherein the combination of rigid means and collapsible means is so constructed and designed as to be less dense than water.

3. The pile protective construction of claim 1 wherein the collapsible means comprises:

a multiplicity of generally cylindrical members secured together, each of said cylindrical members being so constructed and adapted as to expel water normally contained therein at a rate only commensurate with the severity of collision impact for thereby dissipating the impact energy during collapse.

4. The pile protective construction of claim 3 wherein each cylindrical member comprises:

an elongate non-energy storing resilient hollow body normally at least partially filled with water and having a closed upper end and a lower end having formed therein at least one aperture for permitting escape of water therethrough only at a rate commensurate with the severity of impact for thereby dissipating the impact energy.

5. The pile protective construction of claim 4 wherein the rigid means is sufficiently buoyant to buoyantly support the collapsible means.

6. The pile protective construction of claim 4 wherein the collapsible means are constructed and designed normally to contain sufiicient air to buoyantly support the protective construction.

7. The pile protective construction of claim 4 wherein the rigid means comprises:

a multiplicity of shafts secured together by securing means to form an enclosure for being received about the pile.

References Cited UNITED STATES PATENTS 2,722,906 11/1955 Tweddell 114-219 3,104,875 9/1963 Doyle. 3,121,997 2/1964 Sampson 6148 X J. KARL BELL, Primary Examiner U.S. Cl. X.R. 

